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Artificial Intelligence. Dr. Asad Safi Assistant Professor, Department of Computer Science, COMSATS Institute of Information Technology (CIIT) Islamabad, Pakistan. My Introduction . Dr. Asad Ali Safi Assistant Professor Office: 206 Admin block Email: asad.safi@comsats.edu.pk
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Artificial Intelligence Dr. Asad Safi Assistant Professor, Department of Computer Science, COMSATS Institute of Information Technology (CIIT) Islamabad, Pakistan.
My Introduction • Dr. Asad Ali Safi Assistant Professor Office: 206 Admin block Email: asad.safi@comsats.edu.pk Office Phone: 051-90495311
CAMP@TUMChair for Computer Aided Medical Procedures Technical University of Munich, Germany
Course Description Introduction to Artificial Intelligence (AI) history and applications; Strong AI and weak AI Knowledge representation; Problem solving in artificial intelligence using knowledge representation, searching and reasoning; Uninformed and heuristic search; Machine learning; Laws of Robotics; CLIPS programming; Advanced AI Topics. Natural language processing, ANN, Fuzzy logic, clustering
Learning Outcomes Understand the meaning of AI, its alternative approaches and the implications of AI for cognitive science more broadly. Expand knowledge about Inform and uniform search heuristic search, genetic algorithm, planning, and learning algorithms. Understand the basic methods in planning and reasoning using both logic and uncertain inference. Know a variety of ways to represent and retrieve knowledge and information [Expert systems, Agents]. Know the fundamentals of AI programming techniques and advanced machine learning in a modern programming language.
Required Material • Text Book: • Artificial Intelligence: A Modern Approach, Stuart Russell and Peter Norvig, Prentice Hall. • Programming for Artificial Intelligence, CLIPS User Guide • Reference Books: • Artificial Intelligence: Structures and Strategies for Complex Problem Solving, George F. Luger, Addison Wesley Publisher.
Today’s Lecture • What is intelligence? • What is artificial intelligence? • Modern successes • Sentience AI
Let’s begin • Introduction Artificial Intelligence? • AI is one of the newest disciplines • Formally initiated in 1956 • The study of intelligence is also one of the oldest discipline. • For over 2,000 years philosophers have tried to understand how • Seeing • Learning • Remembering • And reasoning could or should be done?????
What is Intelligence ? “ability to learn, understand and think” (Oxford dictionary)
What is Intelligence??? Intelligence is the ability to learn about, to learn from, to understand about, and interact with one’s environment. Intelligence is the faculty of understanding Intelligence is not to make no mistakes but quickly to understand how to make them good (German Poet)
What is Intelligence??? Capacity to learn from experience Ability to adapt to different contexts The use of analyses ability to enhance learning Capacity of mind, especially to understand principles, truths, facts or meanings, acquire knowledge, and apply it to practice; the ability to learn and comprehend.
Intelligence quotientIQ An intelligence quotient, or IQ, is a score derived from one of several standardized tests designed to assess intelligence.
What is artificial intelligence? There is noagreed definition of the term artificial intelligence. However, there are various definitions that have been proposed. Some will be considered below.
What is artificial intelligence? American Association for Artificial Intelligence The scientific understanding of the mechanisms underlying thought and intelligent behavior and their embodiment in machines.
What is artificial intelligence? It is the science and engineering of making intelligent machines, especially intelligent computer programs. It is related to the similar task of using computers to understand human intelligence, but AI does not have to confine itself to methods that are biologically observable. (John McCarthy)
What is artificial intelligence? (ctd.) The use of computers to solve problems that previously could only be solved by applying human intelligence…. thus something can fit this definition today, but, once we see how the program works and understand the problem, we will not think of it as AI anymore (David Parnas)
What is artificial intelligence? (ctd.) • AI is a study in which computer systems are made that think like human beings. Haugeland, 1985 & Bellman, 1978. • AI is a study in which computer systems are made that act like people. AI is the art of creating computers that perform functions that require intelligence when performed by people. Kurzweil, 1990. • AI is the study of how to make computers do things which at the moment people are better at. Rich & Knight, 1991 • AI is a study in which computers that rationally think are made. Charniac & McDermott, 1985. • AI is the study of computations that make it possible to perceive, reason and act. Winston, 1992. • AI is the study in which systems that rationally act are made. AI is considered to be a study that seeks to explain and emulate intelligent behaviour in terms of computational processes. Schalkeoff, 1990. • AI is considered to be a branch of computer science that is concerned with the automation of intelligent behavior. Luger & Stubblefield, 1993.
What’s involved in Intelligence? • Ability to interact with the real world • to perceive, understand, and act • e.g., speech recognition and understanding and synthesis • e.g., image understanding • e.g., ability to take actions, have an effect • Reasoning and Planning • modeling the external world, given input • solving new problems, planning, and making decisions • ability to deal with unexpected problems, uncertainties • Learning and Adaptation • we are continuously learning and adapting • our internal models are always being “updated” • e.g., a baby learning to categorize and recognize animals
Academic Disciplines relevant to AI • Philosophy Logic, methods of reasoning, mind as physical system, foundations of learning, language, rationality. • Mathematics Formal representation and proof, algorithms, computation, (un)decidability, (in)tractability • Probability/Statistics modeling uncertainty, learning from data • Economics utility, decision theory, rational economic agents • Neuroscience neurons as information processing units. • Psychology/ how do people behave, perceive, process cognitive Cognitive Science information, represent knowledge. • Computer building fast computers engineering • Control theory design systems that maximize an objective function over time • Linguistics knowledge representation, grammars
HAL: from the movie 2001 • 2001: A Space Odyssey • classic science fiction movie from 1969 • HAL • part of the story centers around an intelligent computer called HAL • HAL is the “brains” of an intelligent spaceship • in the movie, HAL can • speak easily with the crew • see and understand the emotions of the crew • navigate the ship automatically • diagnose on-board problems • make life-and-death decisions • display emotions • In 1969 this was science fiction: is it still science fiction?
Hal and AI • HAL’s Legacy: 2001’s Computer as Dream and Reality • MIT Press, 1997, David Stork (ed.) • discusses • HAL as an intelligent computer • are the predictions for HAL realizable with AI today? • Materials online at • http://mitpress.mit.edu/e-books/Hal/contents.html • The website contains • full text and abstracts of chapters from the book • links to related material and AI information • sound and images from the film
Consider what might be involved in building a computer like Hal…. • What are the components that might be useful? • Fast hardware? • Chess-playing at grandmaster level? • Speech interaction? • speech synthesis • speech recognition • speech understanding • Image recognition and understanding ? • Learning? • Planning and decision-making?
Can we build hardware as complex as the brain? • How complicated is our brain? • a neuron, or nerve cell, is the basic information processing unit • estimated to be on the order of 10 12 neurons in a human brain • many more synapses (10 14) connecting these neurons • cycle time: 10 -3 seconds (1 millisecond) • How complex can we make computers? • 108 or more transistors per CPU • supercomputer: hundreds of CPUs, 1012 bits of RAM • cycle times: order of 10 - 9 seconds • Conclusion • YES: in the near future we can have computers with as many basic processing elements as our brain, but with • far fewer interconnections (wires or synapses) than the brain • much faster updates than the brain • but building hardware is very different from making a computer behave like a brain!
Can Computers beat Humans at Chess? • Chess Playing is a classic AI problem • well-defined problem • very complex: difficult for humans to play well • Conclusion: • YES: today’s computers can beat even the best human Deep Blue Human World Champion Deep Thought Points Ratings
Can Computers Talk? • This is known as “speech synthesis” • translate text to phonetic form • e.g., “fictitious” -> fik-tish-es • use pronunciation rules to map phonemes to actual sound • e.g., “tish” -> sequence of basic audio sounds • Difficulties • sounds made by this “lookup” approach sound unnatural • sounds are not independent • e.g., “act” and “action” • modern systems (e.g., at AT&T) can handle this pretty well • a harder problem is emphasis, emotion, etc • humans understand what they are saying • machines don’t: so they sound unnatural • Conclusion: • NO,for complete sentences • YES, for individual words
Can Computers Recognize Speech? • Speech Recognition: • mapping sounds from a microphone into a list of words • classic problem in AI, very difficult • “Lets talk about how to wreck a nice beach” • (I really said “________________________”) • Recognizing single words from a small vocabulary • systems can do this with high accuracy (order of 99%) • e.g., directory inquiries • limited vocabulary (area codes, city names) • computer tries to recognize you first, if unsuccessful hands you over to a human operator • saves millions of dollars a year for the phone companies
Recognizing human speech (ctd.) • Recognizing normal speech is much more difficult • speech is continuous: where are the boundaries between words? • e.g., An English professor wrote the words: "A woman without her man is nothing" on the board and asked his students to punctuate it correctly. All of the males in the class wrote: "A woman, without her man, is nothing." All the females in the class wrote: "A woman: without her, man is nothing." • large vocabularies • can be many thousands of possible words • we can use context to help figure out what someone said • e.g., hypothesize and test • try telling a waiter in a restaurant: “I would like some dream and sugar in my coffee” • background noise, other speakers, accents, colds, etc • on normal speech, modern systems are only about 60-70% accurateConclusion: • NO, normal speech is too complex to accurately recognize • YES, for restricted problems (small vocabulary, single speaker)
Can Computers Understand speech? • Understanding is different to recognition: • “Time flies like an arrow” • assume the computer can recognize all the words • how many different interpretations are there?
Can Computers Understand speech? • Understanding is different to recognition: • “Time flies like an arrow” • assume the computer can recognize all the words • how many different interpretations are there? • 1. time passes quickly like an arrow? • 2. “time-flies” are fond of arrows • …
Can Computers Understand speech? • Understanding is different to recognition: • “Time flies like an arrow” • assume the computer can recognize all the words • how many different interpretations are there? • 1. time passes quickly like an arrow? • 2. command: time the flies the way an arrow times the flies • 3. command: only time those flies which are like an arrow • 4. “time-flies” are fond of arrows • only 1. makes any sense, • but how could a computer figure this out? • clearly humans use a lot of implicit commonsense knowledge in communication • Conclusion: NO, much of what we say is beyond the capabilities of a computer to understand at present
Can Computers Learn and Adapt ? • Learning and Adaptation • consider a computer learning to drive on the freeway • we could teach it lots of rules about what to do • or we could let it drive and steer it back on route when it heads for the edge • systems like this are under development (e.g., Daimler Benz) • e.g., RALPH at CMU • in mid 90’s it drove 98% of the way from Pittsburgh to San Diego without any human assistance • machine learning allows computers to learn to do things without explicit programming • many successful applications: • requires some “set-up”: does not mean your PC can learn to forecast the stock market or become a brain surgeon • Conclusion: YES, computers can learn and adapt, when presented with information in the appropriate way
Can Computers “see”? • Recognition v. Understanding (like Speech) • Recognition and Understanding of Objects in a scene • look around this room • you can effortlessly recognize objects • human brain can map 2d visual image to 3d “map” • Why is visual recognition a hard problem? • Conclusion: • mostly NO:computers can only “see” certain types of objects under limited circumstances • YES for certain constrained problems (e.g., face recognition)
Can computers plan and make optimal decisions? • Intelligence • involves solving problems and making decisions and plans • e.g., you want to take a holiday in Brazil • you need to decide on flights • you need to get to the airport, etc • involves a sequence of decisions, plans, and actions • What makes planning hard? • the world is not predictable: • your flight is canceled or there’s a backup on the 405 • there are a potentially huge number of details • do you consider all flights? all dates? • no: commonsense constrains your solutions • AI systems are only successful in constrained planning problems • Conclusion: NO, real-world planning and decision-making is still beyond the capabilities of modern computers • exception: very well-defined, constrained problems
Summary of State of AI Systems in Practice • Speech synthesis, recognition and understanding • very useful for limited vocabulary applications • unconstrained speech understanding is still too hard • Computer vision • works for constrained problems (hand-written zip-codes) • understanding real-world, natural scenes is still too hard • Learning • adaptive systems are used in many applications: have their limits • Planning and Reasoning • only works for constrained problems: e.g., chess • real-world is too complex for general systems • Overall: • many components of intelligent systems are “doable” • there are many interesting research problems remaining
Intelligent Systems in Your Everyday Life • Post Office • automatic address recognition and sorting of mail • Banks • automatic check readers, signature verification systems • automated loan application classification • Customer Service • automatic voice recognition • The Web • Identifying your age, gender, location, from your Web surfing • Automated fraud detection • Digital Cameras • Automated face detection and focusing • Computer Games • Intelligent characters/agents
AI Applications: Machine Translation • Language problems in international business • e.g., at a meeting of Japanese, Korean, Vietnamese and Swedish investors, no common language • or: you are shipping your software manuals to 127 countries • solution; hire translators to translate • would be much cheaper if a machine could do this • How hard is automated translation • very difficult! e.g., English to Russian • “The spirit is willing but the flesh is weak” (English) • “the vodka is good but the meat is rotten” (Russian) • not only must the words be translated, but their meaning also! • is this problem “AI-complete”? • Nonetheless.... • commercial systems can do a lot of the work very well (e.g., restricted vocabularies in software documentation) • algorithms which combine dictionaries, grammar models, etc. • Recent progress using “black-box” machine learning techniques
Summary of Today’s Lecture • Artificial Intelligence involves the study of: • automated recognition and understanding of signals • reasoning, planning, and decision-making • learning and adaptation • AI has made substantial progress in • recognition and learning • some planning and reasoning problems • …but many open research problems • AI Applications • improvements in hardware and algorithms => AI applications in industry, finance, medicine, and science. • Reading: chapter 1 in text,
Simulating 1 second of real brain activity takes 40 minutes and 83K processors Researchers have simulated 1 second of real brain activity, on a network equivalent to 1 percent of an actual brain’s neural network, using the world’s fourth-fastest supercomputer. The results aren’t revolutionary just yet, http://gigaom.com/2013/08/02/simulating-1-second-of-real-brain-activity-takes-40-minutes-83k-processors/
IBM Watson • http://www-03.ibm.com/innovation/us/watson/ • NY Times article • Trivia demo • IBM Watson wins on Jeopardy (February 2011)
Vision • OCR, handwriting recognition • Face detection/recognition: many consumer cameras, Apple iPhoto • Visual search: Google Goggles • Vehicle safety systems: Mobileye
Google self-driving cars • Google’s self-driving car passes 300,000 miles ( 8/15/2012)
Natural Language • Speech technologies • Google voice search • Apple Siri Machine translation • translate.google.com • Comparison of several translation systems
Math, games • In 1996, a computer program written by researchers at Argonne National Laboratory proved a mathematical supposition unsolved for decades • NY Times story: “[The proof] would have been called creative if a human had thought of it” • IBM’s Deep Blue defeated the reigning world chess champion Garry Kasparov in 1997 • 1996: Kasparov Beats Deep Blue“I could feel – I could smell – a new kind of intelligence across the table.” • 1997: Deep Blue Beats Kasparov“Deep Blue hasn't proven anything.” • In 2007, checkers was “solved” • Science article
Logistics, scheduling, planning • During the 1991 Gulf War, US forces deployed an AI logistics planning and scheduling program that involved up to 50,000 vehicles, cargo, and people • NASA’s Remote Agent software operated the Deep Space 1 spacecraft during two experiments in May 1999 • In 2004, NASA introduced the MAPGEN system to plan the daily operations for the Mars Exploration Rovers
Information agents • Search engines • Recommendation systems • Spam filtering • Automated helpdesks • Fraud detection • Automated trading • Medical diagnosis